Suction muffler



' 0d. 1, 19. I u. SAUER 2,216,653

SUCTION MUFFLER Filed July 27,1939 2 Sheets-Sheet 1 Oct. 1, 1940. u, ER 2,216,653

SUCTION MUFFLER Filed July 27, 1939 2 Sheets-$heet 2 Patented Oeti, 1940 SUCTION MUFFLER Urban Sauer, Pittsburgh, Pa.,. assignor of twofifths to Harry R. Levy, McKeesport, Pa.

Application July 27, 1939, Serial No. 286,895

20 Claims.

\ This invention relates to a suction mufiier for internal combustion engines.

The invention aims to provide, in a manner as hereinafter set forth, a mufiler of the class re- 5 ferred to for respectively creating a suction in the exhaust line of the engine to facilitate the scavenging of the burned gases; mufiling and silencing the exhaustnoises; eliminating back pressurein the exhaust line and mufiler; aiding in cooling the exhaust line side of the engine; aiding elimination of carbon deposits; reducing the consumption of fuel by the elimination of back pressure; obtaining increased power by the elimination of the adulteration of the incoming charges of fuel by mixing with burnt gases; increasing the acceleration of the engine due to lessened resistances of gases in the exhaust line and muffier; and materially reducing the discharge of obnoxious smoke from the tail pipe. 29 The invention further aims to provide, in a manner as hereinafterset forth, a suction mufiier for the purpose referred to which is simple in its construction, strong, durable, compact, readily installed with respect to the exhaust of an internal combustion engine, thoroughly efficient in its use and comparatively inexpensive to manufacture.

Embodying the aims aforesaid .and others which may hereinafter appear, the invention consists of the novel construction, combination and arrangement of parts to be more specifically referred to and illustrated in the accompanying drawings wherein are shown embodiments of the invention, but it is to be understood that changes, 5 variations and modifications may be resorted to -which fall within the scope of the invention as claimed.

In the drawings Figure l is a longitudinal sectional View of a suction mufiler in accordance with theinvention,

Figure 2 is a section on line 2-2 Figure 1,

Figure 3 is a fragmentary view in longitudinal section of a modified form of suction muffler in accordance with the invention,

Figure 4 is a side elevation of the intake tnem ber of the injector forming an element of the structure shown by Figure 3, Figure 5 is a section on line 5 5 an enlarged scale,

section of still another modified form,

Figure '7 is a fragmentary view in longitudinal section of another modifiedform of suction muffler in accordance with-this invention,

55 Figure 8 is a fragmentary view 1 Figure 4 upon- Figure 61s a fragmentary view in longitudinal longitudinal section of still another modified form of suction mufiler in accordance with this invention, and

Figure 9 is a section on line 9-9 Figure 8.

With reference to Figures 1 and 2 the mufller l includes a housing or casing 2 formed of a cylindrical rear portion 3, a tapered intermediate portion 4 and a reduced cylindrical forward portion 5 which constitutes the tail pipe or outlet for housing 2. The latter is provided with aclosure 5 at its rear end.

Suspended within the rear part of, spaced from and disposed lengthwise with respect to housing portion 3 is an ejector structure 6 which is adapted to be connected to the exhaust line or outlet (not shown) of the engine. The structure 6 acts to conduct the exhaust from the engine. into themuffler I. The structure 6 includes a sleeve 1 open at each end and disposed axially and lengthwise of housing portion 3. The inner face of sleeve 1 at its forward and rear end-terminal portions is threaded, .as at 1, l respectively. Extending into and threadedly engaging with the threads at the forward end terminal portion of the sleeve '17 is a cylindrical nozzle element 8. The latter is formed of a base or rear portion 9 and a forward discharging portion I 9. The portion 9 is of greater outer diameter than the portion [0 and is formed with threads on its outer periphery for engagement with the forward threads of sleeve 1 whereby the nozzle 8 is connected to and extends forwardly from sleeve 1. The inner face of portion 9 is tapered from its rear to its forward end. The said portion I9 is of greater length than the said portion 9. Threadedlyengaging with the threads on the rear end terminal portion of the inner face of sleeve 1 and extended rearwardly from the latter is a tubular director element H for the exhaust gases and which includes a tapered rear end portion l2, a tapered intermediate portion l3 and a tapered forward end portion 14. The portion I2 has its diameter greater than the diameter of the portion |3.' The portion Hlhas its diameters less thanthe diameters of the portion I2, l3. The

portions l2, l4 are of less length than the length of portion l3. The portion l2 extends outwardly from the rear end of sleeve 1. The portion M is arranged to oppose in spaced relation the inner face of the base portion of the nozzle 8. The

. outer periphery of the portion IQ of the element l I is formed throughout with spaced inclined de-" fleeting blades or vanes ii of any suitable form disposed spirally of the said periphery. The inner face of theportion I4 is formed throughout with spaced inclined deflecting blades or vanes,

disposed opening l1.

notshown, of any suitable form disposed spirally of such face, but preferably these vanes on the inner face of said portion I6 will be of the same form and arrangement as the vanes or blades 5|, Figure 5. The portion I3 of the element II is formed with peripheral threads I I which engage with the rear threads I ofv sleeve 1 whereby the element I is connected to sleeve I. and element I 0 are arranged axially.

The closure is formed with an eccentrically The sleeve 1 between its transverse median and rear end is provided with an opening I8. The ejector structure 6 includes an angle shaped intake pipe I9 for the exhaust gases and which is for communication with the exhaust line or exhaust of the engine. The pipe- I9 includes a pair of legs 20, 2| disposed at right angles to each other. and is fixed to the wall of opening H. The free end of leg 2| isflxed to the wall of opening I8. A support 22 for the nozzle element 8 is arranged in housing portion 3. The pipe I9 in connection with the support 22 suspends the sleeve 1 within and axially of the housing portion 3.

The muflier I. includes a plurality of spaced aligned sets of coaxially arranged annular baiiles of spiral form. Each set consists of an inner bafile 23, an intermediate baflle 24 and an outer baflie 25. The baffles of each set are arranged in spaced relation. As shown by way of example three sets of baffles are employed, but it is to be understood-that the number of sets of baflles may be increased or decreased. The setsi of baflles are secured within housing portion 3 forwardly of the nozzle element 8. The outer bafile of each set is suitably secured to the inner face of housing p rtion 3. Each set of batfles has associated therewith a pair of combined supporting and spacing members 26 consisting of a pair of rods 21 disposed in right angular relation and crossing each other at a d secured together at their centers. The pair of supporting and spacing members for each set are arrangedin abutting relation with the ends of the'baftles of the 9 set. The members 26 are secured, by spot welding to the inner face of housing portion 3 and also to the opposite end of the baiiles and maintain these latter in spaced relation.

The intermediate bafiie of each set coacts with the outer and inner baflies of the set to form the spiral channels'28, 29 of annular cross section. The inner baffle of each set provides an axially arranged spiral passage 30 of cylindrical form in cross section and of a width materially reater than the channel 28 or 29. The channels of one 'set align with the channels of an adjacent set.

The passage of one set aligns with the passage of an adjacent set.

' Secured to the-combined supporting and spacing member 26 at the rear end of the rearmost set of bafiies is a rearwardly extending conoidalshaped deflector 3|. The base of the latten-is anchored to the rods or bars 21.0f such member 26 at equi-distant spaced points from the centers of the said bars 21. The diameter of the base of the deflector3l is less than thediameter of the passage 30 of the rearmost setof bailles and such deflector closes a portion of the intake end of such passage.

The modified form of mufliershownbyFigures 3, 4 and S and indicated, at 32 and its housing or casing 33 is of the same form as the housing 2- with'this exception, that the closure 34 for the rear end of housing 33 is formed with an axially arranged opening 35 in lieu of theeccentrically' The latter The leg 20 extends through' disposed opening I! formed in the closure 5.

The mufller 32 will include spaced sets of baffles 36 of the same arrangement and construction as the sets of baflies employed in the mufiier I. The mullier 32 will also include a deflector 31 of the same form and arrangement as the deflector 3I. The main difference between the mufiier 32 and the mufller I resides in the construction of the ejector structure 38 forming an element of the mufiier 32. 1

The ejector structure 38 includes a nozzle element 39 formed of a forward portion 40 of uniform diameter, an intermediate portion 4| of uniform diameter and a substantially semiovoidal shaped rear portion 42. The element 39 is open at each end. Secured to the inner face of the portion at the forward end portion thereof is a collar 43 having a tapered inner face 44. The forward end of the portion 42 is formed circumferentially thereof with spaced ports 45. The rear end of portion 42 is enlarged and threaded.

The ejectorstructure 38 includes atubular exhaust gas director element 46 which is integral with the forward end of an intake pipe 41 which conducts the exhaust gas to the element 46. The pipe 41 leads from the exhaust line or exhaust, not shown of the engine. The pipe 41 has its forward end arranged in and secured to the wall of opening 35. The element 46 merges into the pipe 41 at the opening 35. The element 46 is ar- 43. The portion 49 opposes in spaced relation the inner face 44 of collar 43. The orward end of portion 49 is flush with the forwa d end of collar 43. The outer face of portion 49 is provided throughout with spaced blades or vanes 50 of any suitable form disposed spirally with respect to such face. The inner face of said portion 49 is provided throughout with spaced blades or vanes 5| of any suitable form disposed spirally with respect to such inner face.

The nozzle element 38 is suspended axially of and within the lrear portion 33 of the housing 32' by a pair of spaced parallel supports 52 through the center of which the element 38. extends. The supports 52 and element 32 are suitably secured together by spot welding.

With reference to Figure 6, the modification relates solely to the form of the bafiles 53 of the and this statement also applies to the passage formed by the inner ba-flie of a set.

It is to be understood that the elements 6 and.

for the channels of the set to be of tortuous form,

8 of t e form shown by Figure 1 and the elements 39 an 44 of the formshown by Figure 3 con stitute what may be termed a nozzle structure. It is furthermore to be understood that the ejector-s B and 38 include as a part thereof a nozzle and a director.

With reference to the modified form shown by Figure 7, it is to be understood that it will include a like arrangement of the spaced sets of coaxially arranged spaced bafiles, and a conoidal shaped deflector as heretofore referred to, but the baiiles and deflector are not illustrated in Figure '7. With reference to the modified form shown by Figure 8 it is to be understood that it will include a like arrangement of spaced sets of coaxially arranged spaced ballles and a conoidal shaped deflector as heretofore referred to, but the bafiies and deflector are not'illustrated in Figure 8. A

structure 5| has as an element thereof a -valve' controlled air supply means arranged coaxially of the element H. The said air supply means consists of a pipe 62 having a tapered forward end portion 63 arranged rearwardly of and in proximity to the said tapered forward end portion M. The pipe 62 extends rearwardly through the opening 60 and is connected to a control valve 64 which is attached to an air supply line 65. Otherwise than that as stated the construction of the ejector structure 6| will conform to the ejector structure 6.

With further reference 66 includes a housing or casing 61 .of the same form of the housing 33 with the exception that the closure 68 for the rear end of housing 6! is formed with an axial opening 69 of greater diameter than the opening 35 and that the rear face of the closure 68 is provided with a collar L0 forming a rearward extension of the wall of opening 89. The inner face of collar Ill and the wall of opening ,69 are threaded as at 10 89 respectively. The ejector structure H employed in the muffler 6B is somewhat similar in construc tion to the ejector structure 38 and the differences of the structure 'H' with respect to the structure 38 will'now be referred to. The nozzle element 12 of the structure 1] has its inter mediate portion 13 and its rear portion 14 of greater length than the portions M, 42 of the nozzle element 39 of the structure 38 and this statement also applies to the length of the director element I5 of'the structure H with respect to the element 66 of the structure 38. The

said intermediate portion l3 at its rearend is provided with peripheral threads 18 and forwardly of said threads with a circumferential row of spaced ports H for the entrance of exhaust gas from housing 61.1 The said intermediate portion 13. conforms in contour to the intermediate portion M of the nozzle element 39'. The said rear portion 14 corresponds substantially in contour to the rear portion 62 of the element 39.

The element 12 extends rearwardly through the opening 69 and collar 10 and the said threads 16 coact with the threads on the wall of opening 69' and on the inner face the ejector structure I! portion of housing 61. element 12 is arranged of collar 10 for securing to and axially of the rear The rear portion Id of rearwardly of collar 10 and itis provided, intermediate its ends with a to Figure 8 the muffler gas coming throughfrom pipe circumferential row of spaced air intake ports 18 controlled by an annular adjustable apertured shutter 19 arranged within and slidably connected .to the said portion 14. The latter is slotted, as at 80 for the passage of an outwardly directed shifting arm 8| for the shutter 19. The portion 14 is open at its rear end and has projecting from such e'ndan interiorly threaded collar 82. The director element 15 of the structure H is not only of greater length than the director element 66, but it extends rearwardly from the element l2 and is formed with peripheral threads for securing it to the threaded collar 82, whereby the elements l2, l5 will be connected together and disposed coaxially. The element 15 is adapted to communicate with the outlet line for exhaust gases from the engine. The forward portion of the element 'l2 is indicated at 83. Otherwise than that as stated the ejector structure H. will conform to the ejector structure 38. Parts'of the structure I! which correspond to parts of the structure 38 are indicated by corresponding reference characters.

With respect to the mufller l, the exhaust gases conducted by the pipe l9 to the ejector structure B will be acted upon by the vanes 15 to impart a spiral movement to the gases which comes to the center of the part Ill of such structure and cause suction on the gases entering the element II which draws any gases in the rear of the which and combined pressure of which will be greater than that of the gas passing through pipe l9 and through the vanes 15. The gases passing through the element II will also add to the spiral movement of the gases in part l0, causing the increased volume and combined pressure I of the gases in part ill to overbalan'ce the gases in the pipe l9 and thereby cause a degree of suction upon the gases in the exhaust line. The part l0 must be of a length sufiicient for the gases to come to the center thereof and the longer the part I0 is, the better the pull.

The overbalancing by the stream of gas in part ID of element 8 may be augmented by 'th'e'introduction of a stream of cold atmospheric air into the centeruof the element ll, because the pressure of the gases in part Ill of-lelement 8 will be increased when, at this point, thestream of cold air mixes with the hot gases, causing an expansion of the cold air and an increase of the pressure thereof. The construction disclosed by Figure 7 provides for the introduction of the air as referred to. The size of the part it! of element 8, permits a getaway of the mixture of hot gas and cold air after'the expansion point. The effect of the increased pressure at such point is to overbalance it to a greater degree the stream of I9, through the ejector nozzle creating a more pronounced suction at the exhaust line than is affected without I the use of the cold air, although, as stated heretofore, the use of the inner stream of warm gas also overbalances the stream of hot gases coming through pipe IS on account of the combined pressure of the increased volume of gas going through the element .ll upon rotatingin part H! of element 8 is greater than the pressure oi the gas coming through pipe l9.

With reference to Figures 8 and 9 a structure is illustrated including an adjustable means which piovides for the use of atmospheric air to create expansions and augment the pressure going through the ejector structure. The use of the outside cold air may be in such volume as desired, either by covering the entire diameter of element 15 or by supplying the air to the center of element ll, inwhich case the exhaust that spreads to the rear part of the muflier will be drawn in through the element 15.

The operation'of the gases, after leavingan ejector structure, whether combined with air or without is 'first to impact the peak of the deflector 3| or 31 and which causes a deflection of the gases, after which they enter passage 30 and the channels 28, 29 of the rearmo'st set of baflles, and then the gases pass through-the passages and channels of the other sets of baiiies. Owing to the arrangement of the baflles of each set, the gases will be spread through the length of the set, and this results in a killing of the sound waves and expansion of the gas, having a necessary silencing effect and yet, eliminating the holdingback of the gas in its course. The flow of the gas towards the exit is not hindered by the use of the baflies of the form as shown.

The spiral courses formed by the baflies of each set willprovide for an additional suction as the gases travel towards the exit end of the muiller, and the tendency of the gases moving in a spiral course and completely filling theavailable spaces between the baflles of each set in a rotary'movement is to create additional suction.

The operation of the mufller 32 will accomplish the same result as the mufller, but in lieu ofsupplying the exhaust gas directly into the element 39 .is supplied directly into the element 46 and the vanes on the inner face of element 46 will impart a spiral movement to the gas as it is discharged from element 46 and provide a suction on the gas which enters element 39 through therethrough the ports 45, The vanes on the outer face'of element 46 will also impart a spiral movement to the gas as it passes between 44, and D to part 40. The latter is to be of the same length as part III for the purpose of providing the gases passing With respect tothe forms of the device shown by Figures land 7, the gas enters into the injector at an angle with respect to the axis of the director and this angle is essential for only in this manner does the pressure of the gas become evenly distributed about the director. The gas is taken directly into the forms of the device shown by Figures 3 and 8, whereby the pressure thereof is naturally evenly distributed when the as reaches the head of thesdirector.

What I claim is:

1. A mufller comprising a housing having an 0ut1et,"a plurality of spaced aligned sets of spaced annular baiiles within-said housing and arranged coaxially, thebafiles of each set being so formed to provide a plurality of coaxially arranged tortuous channels and a tortuous passage disposed coaxially with said channels, and an ejector structure arranged in said housing rearwardly of said sets for receiving exhaust gases and including a nozzle, an internal annulartapered face and a tubular director formed with a tapered forward end terminal portion having its periphery provided with blades lation the said tapered face, saidnozzle extending opposing in spaced re-' forwardly from said tapered inner face.

2. A muflier comprising a. housing having an outlet, a plurality of spaced aligned setsof spaced ,annular baflles within said housing and arranged coaxially, the baflles of each set being so formed to provide a plurality of coaxially arranged tortuous channels and a tortuous passage disposed coaxially with said channels, andan ejector to cause a degree of suction uponthe gases in the exhaust line.

structure arranged in said housing rearwardly of said sets for receiving exhaust gases and including a nozzle, means for directing the exhaust gases into and at an angle with respect to the axis of the director, an internal annular tapered face and a tubular director formed with a tapered forward end terminal portion having its periphery provided with blades opposing inspaced relation the said tapered face, said nozzle extending forwardly from said tapered inner face, the said tapered forward end terminal portion of the director being provided on its inner face with blades.

3. A. mufller comprising a housing having an outlet, a plurality of spaced aligned sets of spaced annular bailies within said housing and arranged coaxially, the baiiies of each set being so formed to provide a plurality of coaxially arranged tortuous channels and a tortuous passage disposed coaxially with said channels, and an ejector structure arranged in said housing rearwardly of said sets for receiving exhaust gases and including a nozzle, an internal, annular tapered face and a tubulardirector formed with a tapered forward end terminal portion having its periph-.

coaxially with said channels, and an ejectorstructure arranged in said housing rearwardly of said sets for receiving exhaust gases and including .a. nozzle, an internal annular tapered face and a tubular director formed with a tapered forward end terminal portion having its periphery provided with blades opposing in spaced relation the said tapered face, said nozzle extending forwardly from said tapered inner face, the said tapered forward end terminal portion of the director being provided on its inner face with blades, the said blades on the inner and outer faces of the said end terminal portion being spirally arranged relative tosuch portion.

5. A mufller comprising .a housing having an outlet, a plurality of spaced aligned sets of spaced annular baffles of spiral form within said housing rearward] of said outlet, the baflles of each set. being arranged coaxially and correlated to provide circular channels having spiral walls. and an annular passage having a spiral wall, said passage disposed coaxially with'said channels, and an ejector structure arranged within the housing rearwardly of said sets for receiving exhaust gases and including a, discharge nozzle and a tubular gas director arranged rearwardly of the outlet end of the nozzle, said director having its axis aligned withthe axis of said passage. 5. A mufller comprising a housing having an outlet, a plurality of spaced aligned sets of spaced annular bailies of spiral form wi hin said housing rearwardly of said outlet, the baffles of each set being-arranged coaxially and correlated to provide circular channels having. spiral walls 70 of the outlet end of the nozzle, said director having its axis aligned with the axis of said passage, said structure provided intermediate its ends with an internal annular tapered surface, and said' director having a tapered forward terminal portion opposing in spaced relation said tapere surface. I

7. A muiiler comprising a housing having an outlet, a plurality of spaced aligned sets of spaced annular bafiies of spiral form within said housing rearwardly of said outlet, the baflles of each set being arranged coaxially and correlated to provide circular channels having spiral walls and an annular passage having a spiral wall, said passage disposed coaxially with said channels, an ejector structure arranged within the housing rearwardly of said sets for receiving exhaust gases and including a discharge nozzle and a tubular gas director arranged rearwardly of the outlet end of the nozzle, said director having its axis aligned with the axis of said passage, said structure provided intermediate its ends with an internal annular tapered surface, and said director having a tapered forward terminal portion opposing in spaced relation said tapered surface,

- the said tapered terminal portion being provided on its inner and outer faces with spirally arranged blades.

8. In a muffler a housing having an outlet, spaced aligned sets of coaxially arranged spaced spiral baiiies within the housing rearwardly of said outlet, and an ejector-structure for receiving exhaust gases, said structure arranged rearwardly of said baflies and including a discharge nozzle and a tubular gas director opening into the nozzle intermediate the ends of the latter.

9. In a muiiier a T' housing having an outlet, spaced aligned sets of coaxially arranged baflies within the housingrearwardly of said outlet, and an ejector-structure for receiving exhaust gases,

said structure arranged rearwardly of said baflies.

and including a discharge nozzle and a tubular gas director opening into the nozzle intermediate the ends of the latter, said director being provided with internally and externally spirally arrangedblades at its leading terminal portion.

10. In a suction muiiier a housing having an outlet, a set of spaced coaxially arranged spaced spiral baffles within the housing rearwardly of the outlet, said baflies correlating to form a, plurality of circular channels having spiral walls, the inner one of said bafiies providing an annular passage having a spiral wall, each of said baffles being so formed to provide interrupted walls for the channels'and the passage,'and an ejectorstructure within the housing rearwardly of the baffles for receiving and directing exhaust gases towards said bafiles.

11. A muiiler comprising a housing having an outlet, a plurality of spaced alignedsets of spaced annular bafiles within said housing and arranged coaxially, the baffles of each set being so formed to provide a plurality of coaxially arranged tortuous channels and a tortuous passage disposed .coaxially with said channels, an ejector structure arranged in said housing rearwardly of said sets for receiving exhaust gases and including a nozzle, an internal annular tapered face and a tubular director formed with a tapered forward end terminal portion having its periphery provided with blades opposing in spaced relation the said tapered face, said nozzle extending forwardly from said tapered inner face, and means for supplying air into said ejector structure.

12. A mufiler comprising a housing having an outlet, a'plurality of spaced aligned sets of spaced annular baflies within said housing and arranged coaxially, the baffles of each set being so formed to provide a plurality of coaxially arranged tortuous channels and a tortuous passage disposed coaxially with said channels, an ejector structure arranged in said housing rearwardly of said sets for receiving exhaust gases and including a nozzle, an internal annular tapered face and a tubular director formed with a tapered forward terminal portion having its periphery provided with blades opposing in spaced relation the said tapered face, said nozzle extending forwardly from said tapered inner face, andmeans for supplying air into said ejector structure, said air supplying means being controllable.

' 13. In a mufiler, a housing having an outlet, spaced aligned sets of coaxially arranged spaced spiral baiiies arranged within the housing, an ejector structure for receiving exhaust gases arranged within the housing rearwardly of said sets, said structure including tubular'means providing a discharge nozzle and tubular means providing a gas director positioned within the rear portion of the said other means, said nozzle and director being coaxially arranged.

14. In a muffler, a housing having an outlet,

portion of and opening into the said other means,

said nozzle and directorbeing coaxially arranged, and means for supplying air into said gas director.

15. In a mufiler, a housing having an outlet, spaced aligned sets of coaxially arranged spaced bailies arranged within the housing, an ejectorstructure for receiving exhaust gases arranged within the housing rearwardly of said sets,.said structure including tubular means providing a discharge nozzle and tubularmeans providing a gas director positioned within the rear portion of and opening into the said other means, said discharge nozzle being provided intermediate its ends and on its inner face with an annular tapered surface, said gas director having its outer terminal'portion of tapered form encompassed by said inclined surface, the tapered outer terminal portion of said director being provided on its inner and outer face with vanes, said nozzle and director being coaxially arranged, and means for supplying air to said nozzle providing means:" 3%

16. In a, mu r, a housing having an outlet, spaced aligned sets of coaxially arranged spaced bafiies arranged within the housing, an ejector structure for receiving exhaust gases arranged within the housing rearwardly of said sets, said structure including tubular means providing a discharge nozzle and tubular means providing a gas director positioned within the rear portion of and opening into the said other means,

said discharge nozzlebeing provided intermediate its ends and on its inner face with an annular 1'7. In a muflier, a housin having an outlet, spaced aligned sets of coaxia ly arranged spaced baffles arranged within the housing, an ejector structure, for receiving exhaust gases arranged within the housing rearwardly of said sets, said structure including tubular means providing a discharge nozzle and tubular means providing a gas director positioned within the rear portion of the said other means, said nozzle and director being coaxially arranged, said nozzle provided with means having a tapered surface intermediate the ends of its inner face, said director having a part of its outer periphery tapered, said tapered part formed with blades opposing in spaced relation said tapered'surface.

18. In a mufller, a housing having an outlet, spaced aligned sets of coaxially arranged spaced baffles arranged within the housing, an 'ejector structure, for receiving exhaust gases arranged within the housing rearwardly of said sets, said structure including tubular means providing a discharge nozzle and tubularmeans providing a gas director positionedvwithin the rear portion of the said other means, said nozzle and director being coaxially arranged, the said ejector structure provided with means for establishing communication between the interior thereof and the interior of they rear portion of said housing, said nozzle provided therein with means having a tapered surface intermediate the ends of its inner face, said director being formed withblades at the forward end portion of its outer face opposing in spaced relation said tapered surface and with blades on the forward end portion of the inner face.

19. A muflier comprising a housing having an outlet,baflling means within said housing rearwardly of said outlet for the passage of the exhaust gases, and an ejector structure for injecting gases into said means, said structure arranged in said housing rearwardly of said means, and including a sleeve having an internal tapered surface, a nozzle extended forwardly from said surface and a tubular director axially of said sleeve for receiving the exhaust gases formed with a tapered end terminal portion having its periphery provided with blades opposing in spaced relation the said surface.

20. A muflier comprising a housing having an outlet bafliing means within said housing rearwardly of said outlet for the passage-of the exhaust gases, and an ejector structure for injecting gases into said means, said structure arranged in said housing rearwardly of said means, and

including a sleeve having an internal tapered surface, a nozzle extended forwardly from said surface and a tubular director axially of said sleeve for receiving the exhaust gases formed with a tapered end terminal portion having its periphery provided with blades opposing in spaced relation the said surface, and means extending into the housing for directing the exhaust gases into and at right angle to the director. URBAN SAUER. 

